Pumping equipment

ABSTRACT

Pumping equipment for lowering the level of liquids in boreholes and the like and comprising a pump unit which is designed for location in such a borehole and for operation by an air pulse supply unit located externally of the borehole at ground or other convenient level. The pump unit comprises a tubular body which is sealed at one end and is provided at the other end with a liquid intake controlled by a one way valve, a discharge tube one end of which is disposed in the tubular body and is equipped with a one way valve while its other end is adapted to be connected to a discharge hose leading from the pump unit to a discharge point externally of the borehole and a connection on said tubular body to which an air supply line from the air pulse supply unit may be attached so that air may be supplied periodically to the interior of the tubular body.

0 United States Patent [151 3,647,319 McLean et al. 1 Mar. 7, 1972 [54] PUMPING EQUIPMENT 2,777,399 1/1957 Clark ..417/ 149 3,092,143 6/1963 Denman .l37/624.14 m] lnvenms' g xfggfgg z g bmh 3,288,081 11/1966 McMillan ..417/147 73] Assignee: Terresearch Limited, Northolt, Middlesex, Primary Emminercorlioh Croyle England Assistant Examiner-R1chard E. Gluck A1torney--Waters, Roditi, Schwartz & Nissen [22] F1led: Jan. 21, 1970 [21] Appl. No.2 4,539 [57] ABSTRACT Pumping equipment for lowering the level of liquids in boreholes and the like and comprising a pump unit which is [30] Foreign Applicauon Priority Data designed for location in such a borehole and for operation by Feb. 6, 1969 Great Britain ..6,582/69 an air pulse supply unit located externally of the borehole at ground or other convenient level. The pump unit comprises a [52] U.S. Cl. ..417/143, 417/144, 417/146, tubular y which is sealed a ne end and is provided at the 137 24 14 other end with a liquid intake controlled by a one way valve, a 51 1111.01. ..F04t 3/00, F04f 1/06 discharge who one end of which is disposed in the tubular 58 Field of Search ..417/109, 115, 118, 137, 143, body and is q pp with a one y valve while its other end 417/144, 145, 146 137/624'14 is adapted to be connected to a discharge hose leading from the pump unit to a discharge point externally of the borehole "has and a connection on said tubular body to which an air supply [56] Rate cued line from the air pulse supply unit may be attached so that air UNITED STATES PATENTS may be supplied periodically to the interior of the tubular bod 1,724,858 8/1929 Small ..417/143 X y 984,329 2/1911 Weber ..4l7/123 2 Claims, 3 Drawing Figures PUMPING EQUIPMENT This invention relates to pumping equipment which is suitable for use in civil engineering and other activities for lowering the level of liquids such as water in boreholes and the like.

When space permits and where a suction lift is practicable there is a wide range of pumps already available but if space is restricted e.g., in a shaft, well or borehole and if the lift is greater than can be achieved by suction then the choice of pump type is at present very restricted.

Of the pumps available there is the electric submersible pump which comprises essentially a centrifugal pump powered by an electric motor the construction being such that the pump and motor may be immersed in the liquid to be pumped. In the casewhere such a unit is intended for use in a shaft, well or borehole it has to be extremely compact and built to close tolerances especially where a high pumping head is.involved. The pump is susceptible to wear caused either by corrosion due to ground water or to the presence of fine soil particles in the liquid being pumped. Furthermore due to-the weight of the unit a crane or hoist is necessary when the unit is installed and removed for servicing.

In addition to the electric pump there is a compressed air driven centrifugal pump, the actual pump being driven by a compressed air motor. The range of these pumps commercially available precludes their use in a well or borehole of less than 12- inch diameter and they are susceptible to wear as in the case of electric pumps and moreover they also require to be removed for maintenance purposes.

There is also a compressed air sludge pump available but this is heavy, large and easily affected by grit and corrosion. While such pumps are widely used in open excavations or relatively large shafts they are too large for use in small boreholes.

Again in certain circumstances a so-called air lift system may be employed. This system is simple in use but as it depends on the relative weights of liquid and or air/liquid mixture it is not possible completely to dewater an excavation unless the well or shaft used to install the air lift extends to a cons'iderable depth below the level to which the liquid has to be lowered.

It is the chief object of the present invention to evolve a pump which will overcome the various limitations referred to above and will also be capable of providing a pumping arrangement for use in circumstances other than those referred to above.

According to the present invention it is proposed to provide a pump unit having a connection for a discharge hose or the like and an air inlet connection which is adapted to be coupled to an air pulse supply unit located at a point removed from the pump. Preferably the pump unit will comprise a tubular body having a liquid intake at one and controlled by a one-way valve such as a ball valve, the other end of such body being closed by means of a closure plate, cap or the like which is provided with the air inlet connection and through which passes a tube to the outer end of which the discharge hose or the like is attached, the inner end of such tube, which is located within the tubular body, being equipped with a oneway valve such as a ball valve. Preferably the air pulse supply unit will incorporate means whereby the period of air supply to the pump and the time lapse between periods of air supply may be varied or controlled to suit any particular circumstances. By separating the pump from the air pulse supply unit it will be possible to locate the latter at a convenient point e.g., at ground level or above so that an operator will have ready access thereto for control, adjustment and maintenance without having to move the pump from the position in which it is installed.

In order that the said invention may be clearly understood and readily carried into effect reference will now be made to the accompanying diagrammatic drawings in which:

FIG. 1 illustrates diagrammatically a pump installation in accordance with the invention,

HO. 2 shows in section a pump unit according to the invention, and

FIG. 3 shows diagrammatically one possible air pulse supply unit.

. sure not shown.

As will be seen from HO. 2 the pump unit comprises an outer tubular body 16 which is provided at its lower end, adapted to constitute the liquid intake end, with a perforated cap or strainer I7. Also at its lower end the body I6 is provided with a seating I8 for a ball 19, the arrangement being such that normally the ball will tend to assume its seated or closed position under the action of gravity. The tubular body is closed at its upper end by means of a sealing plate, cap or the like 20 which is provided with a connection 21 for the air line 13 through which air under pressure will be supplied to the pump from the air pulse supply unit above referred to. Also passing through the closure plate or cap 20 is a tube 22 to the outer end of which the discharge or delivery hose 12 is connected. The tube 22 which extends downwardly into the tube is provided at its lower end with a ball valve 23.

The means for providing for air pulsation to the pump to effect operation thereof may take many forms but a convenient pulse supply unit is indicated diagrammatically by way of example in FIG. 3. Referring now to that Figure, 24 denotes a three-part diaphragm operated valve which is provided with a connection for the line 15 communicating with the source of compressed air with a connection for the line 13 leading to the pump and with an exhaust port 25 to atmosphere. Normally the valve 24 will assume a position such that the passage of compressed air to the air line 13 will be cut off by a closed path 24A while said air line 13 will be connected via a'flow path 24B to the exhaust port 25 i.e., to atmosphere. On actuation of the valve 24 a connection will be established, via a flow path 24C, between the lines I5 and 13 so that air will be supplied to the pump, the exhaust port then being closed by a closed path 24D.

To control the operation of the valve 24 a secondary valve designated generally by 26 is provided such valve being equipped with diaphragm actuators 27 and 28 the operation of which is in turn controlled by needle valves 29 and 30. The valve 26 has flow paths 26A, 26B, 26C and 26D and closed paths 26E and 26F formed in its body, which body is displaceable, by the actuators 27 and 28, to select the'ports to be placed in communication with these paths.

The pumping cycle will be as follows:

With the diaphragm valve 24 in its normal, illustrated, position and the pump submerged in liquid in the borehole, the ball 19 and possibly also the ball 23 within the pump body will be lifted from their seatings allowing liquid from the borehole to enter the pump body. Due to the fact that at this time the air line 13 is connected to the exhaust port 25 of the valve 24 via the valve flow path 248, air present in the pump body will be displaced by the inflowing liquid via said line and also through the discharge or delivery hose 12. As soon as the level of liquid within the pump and possibly the hose and air line and outside the pump has reached a balanced condition the ball valves 19 and 23 will fall back on to their seats and close.

During this pump filling part of the cycle the valve 26 is also in the illustrated condition and compressed air from the supply line 15 will flow via the flow path 26B of the valve 26 and the adjustable needle valve 29 to the actuator 27 ,of the secondary valve 26. In this condition a line from the actuator of the valve 24 is connected to exhaust via the flow path 26A of the valve 26 and the flow paths of 26C and 26D of the valve 26 are ineffective. The needle valve 29 may be adjusted to vary the rate at which air is supplied to the actuator 27 of the secondary valve. As soon as sufficient air has been supplied to the actuator 27 the secondary valve 26 will be actuated so that its body is displaced to a position that allows air to pass from the line 15 via the flow path 26C to act on the diaphragm of the valve 24, the actuator 28 first exhausting via a ball valve 32 and the flow path 26A. In this displaced condition of the valve 26 the path to the needle valve 29 and a ball valve 31 parallel thereto is connected via the valve flow path 26D to exhaust and the flow paths 26A and 26B are ineffective. The connection of the ball valve 31 to exhaust, as in the case of the ball valve 32 mentioned above, allows rapid discharge or escape of air from its associated actuator at appropriate time, thereby allowing smooth operation of the valve 26. With suflicient air pressure on its diaphragm, the valve 24 will be actuated to cause the air supply line 15 to be connected to the line 13 via the flow path 24C so that compressed air will then be supplied to the pump body. The exhaust port 25 is closed by the closed path 24D. Compressed air passing into the pump body will force liquid present in the latter past the ball valve 23 and thence via the tube 22 into the delivery or discharge hose 12.

A further advantage of the system above described resides in the self-cleaning action obtained in the pump unit. Should the ball valve 19 for any reason fail to seat on the valve seat 18, in-rushing air received from the supply line 13 will cause water normally contained in the body 16 to be driven out through the seat 18 past the ball 19 thereby purging the valve seating of any foreign matter which may obstruct the ball valve from returning to the seat. Water will again reenter the pump and this action will continue without interference to the air pulse supply unit until the obstruction is cleared whereupon the pump will return to its normal function.

The valve arrangement of the air pulse supply unit is such that when air is supplied to the diaphragm of the valve 24 there will also be a flow of air via the needle valve 30 to the actuator 28 of the secondary valve 26. As before this needle valve 30 will be adjustable to vary the rate at which air is supplied to this actuator requirement When sufficient air has been discharge to the actuator 28 the secondary valve 26 will be restored to its initial, illustrated, position thereby causing the air supply to the diaphragm of the valve 24 to be cut off whereupon the valve 24 will be restored to its initial, illustrated, condition with the supply of compressed air to the line 13 cut off and the latter again connected to atmosphere via the exhaust port 25 of the valve 24. At this point the pump will be allowed to flood or fill again in readiness for the next pumpmg.

By virtue of the presence of needle valves 29, 30 it will be possible to control both the time lapse between pumping and the period of pumping and thus it will be possible to ensure that the pump will function economically even if the rate of liquid inflow is low. Also since the discharge time may be varied it will be possible to adjust the time requirement to allow for the full discharge of liquid from any depth within the range of to 300 feet. 7

By separating the pump body from its actuating air pulse supply unit it is possible to provide a pump suitable for use in small diameter boreholes and shaped to facilitate easy passage through such boreholes. Furthermore pump units of different size and shape may be used with any air pulse supply unit which may be employed or available. As will be seen a pump unit in accordance with the invention is simple and relatively cheap to make and in the event of its loss down a borehole, or damage, the cost of replacement will not be prohibitive. Furthermore by separating the pump from the air pulse supply unit it is possible to install the latter in a position such that control and maintenance thereof will be a simple matter and once it is established it will be unnecessary to remove the pump from its operative position until such time as the work required from it is completed. Again one air pulse supply unit may be used in conjunction with a series of pumps, by utilizing a selector to direct the pulsating airflow to any particular pump.

While the particular air pulse supply unit above described is convenient any other form of unit may be provided, such unit preferably being of a form such that provision will be made both for variation or control of the time lapse between pumping and the period of pumping.

We claim:

1. Pumping equipment for lowering the level of liquids in boreholes or the like, such equipment including an air pulse supply unit for location externally of a borehole 'or the like, a pump unit designed for positioning in such borehole or the like, an air supply line connected between the air pulse supply unit and the pump unit, and a discharge hose leading from said pump unit to a discharge point externally of the borehole, said pump unit comprising a tubular member which is sealed at one end and is provided at the other with a liquid intake controlled by a one-way valve, a discharge tube one end of which projects into the tubular body and is provided with a one-way valve while the other communicates with the discharge hose and a connection on said tubular body to which said air line is attached so that on operation of the air pulse supply unit air will be supplied periodically to the interior of the tubular body to effect operation of the pump unit, means incorporated in said air pulse supply unit for varying the period of air supply to the pump unit and the time lapses between periods of supply as required, and said means comprises a diaphragm operated valve controlling the supply of air to the pump unit and a secondary valve for controlling the operation of said diaphragm operated valve, said secondary valve comprising a displaceable valve body, a diaphragm actuator at each end of said valve body, an adjustable needle valve for each diaphragm actuator for controlling the flow of actuating fluid to each diaphragm actuator.

2. Pumping equipment as in claim 1 in which the secondary valve also includes means which will allow for rapid escape of actuating fluid from the actuator at appropriate times thereby to allow smooth operation of the secondary valve. 

1. Pumping equipment for lowering the level of liquids in boreholes or the like, such equipment including an air pulse supply unit for location externally of a borehole or the like, a pump unit designed for positioning in such borehole or the like, an air supply line connected between the air pulse supply unit and the pump unit, and a discharge hose leading from said pump unit to a discharge point externally of the borehole, said pump unit comprising a tubular member which is sealed at one end and is provided at the other with a liquid intake controlled by a one-way valve, a discharge tube one end of which projects into the tubular body and is provided with a one-way valve while the other communicates with the discharge hose and a connection on said tubular body to which said air line is attached so that on operation of the air pulse supply unit air will be supplied periodically to the interior of the tubular body to effect operation of the pump unit, means incorporated in said air pulse supply unit for varying the period of air supply to the pump unit and the time lapses between periods of supply as required, and said means comprises a diaphragm operated valve controlling the supply of air to the pump unit and a secondary valve for controlling the operation of said diaphragm operated valve, said secondary valve comprising a displaceable valve body, a diaphragm actuator at each end of said valve body, an adjustable needle valve for each diaphragm actuator for controlling the flow of actuating fluid to each diaphragm actuator.
 2. Pumping equipment as in claim 1 in which the secondary valve also includes means which will allow for rapid escape of actuating fluid from the actuator at appropriate times thereby to allow smooth operation of the secondary valve. 